Gripper for printing-presses



(No Model.) 3. sneets-sh eet 1,

' 0. WENDTE.

GRIPPER FOR PRINTING PRESSES, &c.

No. 549,282. Patented Nov. 5, 1895.

1 lNVENTOH f 61 WITNESSES:

B) j r W l I ATTORNEY.

3 Sheets-Sheet 2.

(No M0de1.)-

W. G. WENDTE. GRIPPBR FOR PRINTING PRBSSES, 8w.-

Patented Nov INVENTOH W/TNESSESr ATTORNEY.

ANDREW lGRANAM,PNOTO-LH'NQWEHINGWKEC,

3 u e e h S s t e e h s 3 c & S B S 8 .EM TP EH N .I m C R 0 WP R E P PI R G n. d 0 M nu W fgiegted Nov. 5, 1895.

' INVENTOH v WITNESSES: j ,4 4' 4 Y x I, hr?

; ATTOHNE positions.

UNITED STATES PATENT OFFICE.

WILLIAM QWENDTE or BOSTON, MASSACHUSETTS.

GRIPPER FOR PRlNTlNG-PRESSES, 8LC.

SPECIFICATION forming part of Letters Patent No. 549,282, dated November5, 1895. Application filed July 24,1895- Serial No. 557 ,024. (Nomodel.)

To all whom it may concern:

Be it known that 1, WILLIAM C. WnNn'rn, a citizen of the United States,and a resident of Boston, in the county of Suffolk and State ofMassachusetts, have invented a new and useful Improvement in Grippersfor Printing-Presses and Like Machines, (Case J of which the followingis a specification.

This invention is related to a large class of contrivances for conveyingsheets of paper or of any similar thin material, and it is especiallyadapted for seizing and holding with precision the sheets fed toprinting-machines designed to give accurate register and uniformmargins.

It is known that the manner in which sheets are taken by grippers of theusual construction has often an injurious influence upon the work. Thisis due chiefly to the oblique manner in which the gripper-fingers strikethe leading edge of the sheet, and that this obliquity is inevitable isobvious when it is remembered that the gripper-shaft must be below thecylinder-surface. In the grippers I have invented the sheet is graspedby an up-and-down movement coincident in direction with a radius of thecylinder and takes the edge of the sheet as it is presented.

In the drawings which form a part of this specification, Figure 1 is aplan view of my gripper within' a cylinder-gap, together with theactuating cams and levers. Figs. 2 and 3 are elevations of the ends ofthe grippercylinder with the outside devices that control the grippermovement. Figs. 4, 5, and 6 are partial cross-sections of the samecylinder-gap, showing the gripper in different Fig. 7 illustrates amodified bearing for the gripper-shaft. Fig. Sis an adjustablegripper-finger. Fig. 9 is a sketch of the tumbling gripper in common usefor purposes of comparison. Fig. 10 compares geometrically the twogrippers in one gap.

In the drawings the fingers 10 are shown attached to the gripper-shaft12. The ends of this shaft do not pass, as usual, through the ends ofthe gap, but are journaled in bearings in the arms 14, fast on the longrockshaft 16, which has bearings in the lug 18 and cylinder end 20,beyond which latter it projects. Outside the end this shaft 16 isprovided with the'arm 24, carrying the roller 26,

which follows the face of the stationary cam 28, attached to the frame30, while contact therewith is maintained by the strong spring 32. Theresult of this arrangement is to cause the shaft 16 to rock as thecylinder revolves and through the arms 14 to raise and lower thegripper-shaft 12 in a direction coincident with or parallel to a radiusof the cylinder and with it the fingers 10 attached thereto.

In my invention the movement just described is that which seizes andholds the paper; but as it is also necessary that the fingers shall getout of the way and disappear below the cylinder-surface 1 use otherdevices for the accomplishment of that purpose which operate with everyrevolution of the cylinder. This disappearance of the fingers is broughtabout by throwing them back in the gapa movement which requires thepartial rotation of the gripper-shaft 12 in its bearings in the arms14:. To accomplish it, a short rock-shaft 34 is j ournaled in the nearcylinder end 22,which is concentric, or nearly so, with the longrock-shaft 16. It carries on its inner end one member of thesegmentgearing at 35, the other being on the grippershaft itself.Outside the short rock-shaft is provided with the arm 36 and roller38,which latter traverse the cam 40, while the spring 12 on thegripper-shaft keeps the stop 14 on each finger up to the gripper-edge ofthe cylinder. In this way I bring the gripper-fingers suddenly forwardat the right moment to a position over the leading edge of the sheet,and an instant before their stops strike the cylinder-edge their promptdescent upon the paper begins under the influence of the spring In Fig.9 the old form of gripper is shown for comparison, and in Fig. 10 theold and new are represented geometrically together in the same gapanentirely suppositious but instructive presentation of the two grippers.In this diagram both grippers are closed, as shown by full lines, dottedlines being used to indicate their positions when open and the pathsdescribed by the extreme point of each.

In the drawings, Figs. 2 and 3 are end elevations of the near and offsides of the cylinder, respectively, with the fixed cams, outside leversand rollers, also-thestrong spring 32 in Fig. 3, which closes thegrippers; also, the relative positions of the same with the essentialdetails within the gap, and with a common delivery-cylinder at 46. Thefeedboard from which the sheets are taken is also shown in these figuresat 48.

In the three sectional Figs. 4, 5, and 6 my gripper is shown in threepositions-namely, with the fingers lifted and thrown back, then with thefingers brought forward till the stop 4.4: has struck the cylinder andfinally after the shaft 12 has dropped and the returnedends of thefingers have seized the paper. In these figures, 50 is the clamp whichholds the blanket or packing when it is bent over into the gap, thefunction of which is well understood.

In Fig. 8 I have shown the adjustable finger which, when desired, I havefound serviceable in this construction. It consists of a steel blade 52,bent at right angles and caught in the clamp 5a, which is controlled bythe screw 56. These blades have a little play and are pressed downintoperfect contact with their seats 011 the cylinder before the screws 56are set up. For accurate adjustment as regards their length, andtherefore the hold these fingers take upon the paper, they greatlysurpass the older form. ()n the gripper-shaft 12 the collar 57, which ispart of the finger-arm 54:, is held by the set-screw 59 on said shaft.

In the foregoing I have represented the stationarycams 28 on the offside of the press, which determines the closing of the gripper, and 40on the near side, which gives it the tumbling motion, as sufiicient fortheir purpose. This is true under ordinary circumstances; but in veryrapidly-running presses I secure greater promptness of action bymodifying these cams as follows: In place of fixing the cams upon theframe they are put free upon the cylinder-shaft, or any bearingconcentric therewith, and held in that position by the rods 58 for thenear and 60 for the off cam. fore; but by connecting the lower ends ofthe suitably-formed rods with cams on any convenient shaft below (notshown) an impulse may be given to the tumbling or to the closing cam, asthe case may be, at the moment when the roller traversing its face fallsor rises, whereby the steepness may be greatly increased 111 effect andthe cams promptness of action enhanced to almost any extent. This willbe evident when it is remembered that the effect of such a suddenvibration of the cam is made to take place at the moment when the rolleris descending a steep incline will be to pull the incline from under theroller, thereby increasing its relative speed very greatly and producingan effect which would otherwise require an exceedingly abrupt projectionon the cam-face. I shall call these rods impulseq'ods.

Having described my invention I wish it So held, the cams behave as be-I to be understood that I do not restrict myself to the specific devicesshown, being well aware that like results may be achieved by other meansand modifications of the apparatus I have employed without departingfrom the principle on which my invention rests. I prefer, for instance,to make the bearing for the gripper-shaft in the arms upon anindependent rock-shaft for the purpose of raisin g and lowering saidbearings; but the gripper-shaft may be otherwise supported and the longrock-shaft itself dispensed with, as

is shown in Fig. 7. In this case the grippershaft 12 entersradially-sliding blocks 57 in the cylinder ends 20 and 22,which furnishbearings for the same. The shaft passes through and beyond each bearingand carries at each end outside the gap a roller 58, which rests uponthe cam 60, and is held down by the stiff spring 62, which correspondsin function to the spring 32 in Figs. 1 and By the action of this camthe bearing-block. 57 are thrown up and dropped again and with them theshaft and fingers on it, as in the former method, whenever it becomesnecessary to release or seize the paper. In Fig. 7 the gripper-fingers10 (shown dotted in the drawings) have just been thrown back by the cam64, over which the roller 66 at the end of the arm is carried. This armis fast on the gripper-shaft and vibrates the same in its bearings atthe proper times. The coilspring 70 (shown dotted as it is in the gap)keeps the stops 44 up to the cylinder edge, as before, when the fingersare above the paper ready for descent upon the edge of the sheet.

There are many advantages gained by my invention, the principal onebeing the up-an ddown motion of the gripper-finger as it seizes orreleases the paper, to which it imparts no impulse of a disturbingnature; also may be cited the very small distance beyond thecylinder-surface within which the fingers move when thrown over. Figs. 9and 10 serve to facilitate in this regard a comparison of the new withthe old construction of gripper. This, as is well known, is often amatter of the greatest importance in pressmachinery of certain kinds.This gripper has been spoken of as moving radially. Practically this isalways true, but of course when theshaft 12 rises and falls with itsbearings, as seen best in Figs. 1 and 3, it passes through anexceedingly small arc, and the tangential part of the finger (the stopon the radial part being heldin contact with the cylinder edge by thespring 42) through an are much smaller. The versed sine of the larger ofthese arcs will he actually about two one-thousandths of an inch, andthat amount will be the shafts maximum depart ure from its true path,which may therefore in direction be spoken of as coincident with acylinder radius or parallel thereto without any appreciable error.

In this specification when the near side of a press or end of animpression-cylinder is referred to, that side or end is meant at whichthe feeder stands, and by the off side or cylinder end the side or endthat is opposite to him is to be understood.

WVhat I claim is- 1. The combination with a cylinder of a gripper shaftplaced diametrically under the gripper edge of the/gap; with fingersrigidly attached thereto; with means for moving said shaft to and fromthe gripper edge while still in the same diametric plane; and with meansfor oscillating it angularly thereby carrying the contact ends of thegripper fingers to and from the gripper edge; substantially asdescribed.

2. An up-and-down gripper for printing machines consisting of agripper-shaft in the cylinder gap journaled in radially moving bearingsand provided with fingers adapted to fall upon and hold the paper; incombination and in operative connection with two cams on thepress-frame, one to lift and lower said bearings, and one to rock thegrippershaft therein and throw its fingers above and into the gap at theproper times; substantially as described.

3. An up-and-down gripper for printing machines consisting of a grippershaft in the cylinder gap journaled in radially moving bearings andprovided with fingers adapted to fall upon and hold the paper; incombination and in operative connection with two cams on the cylindershaft, one to control the up-and-down motion of the gripper shaftbearings, and the other that of the rocking of said shaft therein; andwith impulse-rods to hold and to oscillate both cams in acceleration ofthe specific movements which said cams give rise to; substantially asdescribed.

4. An up and down gripper mechanism for printing presses, consisting ofthe following elements: a gripper shaft within the cylinder gap incombination with a parallel rock-shaft bearing arms in which the grippershaft is journaled; with a cam fixed upon the press frame in operativeconnection with and for the oscillation of the rock-shaft; with gripperfingers fast to the gripper shaft the contact ends of which are bent atright angles to the path in which the gripper shaft rises and falls;with-a pair of segment gears connecting the gripper shaft and a shortshaft placed concentrically with the rock-shaft and with a secondstationary camuponthe press frame by which said short shaft iscontrolled and oscillated and through which the gripper fingers receivetheir angular throw, causing them to appear above the cylinder surfaceand disappear below the same at the proper times; substantially asdescribed.

5. In an up-and-down gripper mechanism a gripper finger adjustable inlength, consisting of a collar and finger arm provided with a set-screwto hold it in place upon the gripper shaft; in combination with aterminal blade one end of which isadapted to fall flat upon the cylindersurface, and the other to clamp adjustably upon the finger arm;substantially as described.

6. A gripper mechanism for printing presses consisting of a number ofgripper fingers, the contact ends of which are bent at right angles, incombination with and attached rigidly to agripper shaft oscillating inbearings that rise and fall; with a cam upon the press frame to controlthe rise and fall of said bearings and thereby lift and drop saidfingers in a line coinciding with their length and at right angles withtheir contact ends; with mechanism for partially rotating the grippershaft at proper times; with a second cam on the press frame forcontrolling said mechanism, whereby the paper is seized and releasedflat by the contact ends of the fingers and the whole mechanism iswithdrawn below the cylinder surface when not functionally operative;substantially as described.

WILLIAM C. WENDTE. Witnesses:

SAMUEL J ENNISON, FRANCIS TODD.

